Material cracking - fixable or a loss?

[Uncle_Lou]

So a couple of years ago I was still learning my way around turning, and decided I wanted to try making a deer call. Ordered the kit from Penn State and my stepdad had a scrap piece of ebony kicking around. I wasn't really considering the properties of the wood in relation to how the piece would be used; I thought the ebony would look and sound really nice for the call. Got it drilled out and turned, finished it with a very light coat of natural danish oil to try to protect the wood and gifted it to a good friend who is an avid hunter. He loves it, says it sounds great and he has successfully called in a number of nice deer with it.

Fast forward to yesterday, I got a text from him with some photos. The call is cracking with the grain in a couple of places. I am assuming that transition from warm to cold and/or dry to humid caused the wood to change shape to the point where it could not handle the stress and cracked. My question is this: Is it fixable and if so, what is the best way to do so? Also, is it possible to prevent further cracking? Or is this something to chalk up as a learning experience and move on?

Attached are some photos of both the completed piece and the cracks. Thanks in advance!

 

[carlmorrell]

I had a daily carry pen out of ebony for years. It cracked, and I filled in the gaps with a crushed stone filler. Still have the pen, things did not get any worse.

 

[jttheclockman]

Fixable? anything is fixable with different ways to do it. As far as preventing, no. That is a wood that is prone to crack and with different conditions as you mentioned is tough to stop no matter what type finish put on it. That piece sees alot more different temp swings and probably wet and dry conditions.

 

[its_virgil]

Ebony is a cracker. There are too many other woods to use than to use those that are prone to cracking.

 

[sorcerertd]

My first thought was that it would be best filled with a contrasting material like Carl has shown with his pen. To keep it subtle on the other hand, some dark smoky resin with a tiny bit of shimmer would look nice, too. I much prefer African Blackwood over ebony for the workability and stability.

 

[Uncle_Lou]

Fixable? anything is fixable with different ways to do it. As far as preventing, no. That is a wood that is prone to crack and with different conditions as you mentioned is tough to stop no matter what type finish put on it. That piece sees alot more different temp swings and probably wet and dry conditions.

Yeah, unfortunately as I said I had not given any real forethought to the properties of the wood when I turned the piece. Definitely a learning moment there. You mentioned there are different ways to approach a fix; what would you recommend? I hate to lose the piece entirely, but it may be too late at this point.

 

[Uncle_Lou]

Ebony is a cracker. There are too many other woods to use than to use those that are prone to cracking.

Well, like I said I was relatively new to turning at the time and had not considered nor was I really aware of the properties of the wood used. Live and learn!

 

[jttheclockman]

Yeah, unfortunately as I said I had not given any real forethought to the properties of the wood when I turned the piece. Definitely a learning moment there. You mentioned there are different ways to approach a fix; what would you recommend? I hate to lose the piece entirely, but it may be too late at this point.

Ways to fix. Fill with some stone material or shavings. Fill with epoxy resin colored black to blend in. One way is to celebrate the cracking and the other way to try to hide it. create sanding dust from scrap piece and create a slurry and mix with epoxy glue (black) and then sand to shape. I never tried it but maybe fill with black CA and then sand it.

 

[GFHWoodWerks]

Yeah, unfortunately as I said I had not given any real forethought to the properties of the wood when I turned the piece. Definitely a learning moment there. You mentioned there are different ways to approach a fix; what would you recommend? I hate to lose the piece entirely, but it may be too late at this point.

You could look at a CA fix. Although I'm not fully sure how CA and Ebony. It should be able to wick into the crack, then lightly clamp it until it bonds then maybe CA finish to try to seal it. I know others have used CA finished in Ebony.

 

[WriteON]

Ways to fix. Fill with some stone material or shavings. Fill with epoxy resin colored black to blend in. One way is to celebrate the cracking and the other way to try to hide it. create sanding dust from scrap piece and create a slurry and mix with epoxy glue (black) and then sand to shape. I never tried it but maybe fill with black CA and then sand it.

I kew a cue maker that specialized in ebony cues...once in a while a player would break their cue by abuse. The cue maker did perfect repairs putting 2 pieces back together. Then crack can flawlessly repaired...Experiment.

 

[leehljp]

Epoxy would be the best bet.

I just would not make a duck or deer call from ebony unless a written note on taking care of it were given. Ebony will crack. Because it is black it will heat faster in sunlight on the side facing the sun and expand more in one spot than the other. When duck and deer hunting, there are so many variables and multi-tasking thoughts that are necessary - to the point that the call's care are way down the list. Wind, noise blind, shot gun/rifle, ammunition, sound, etc. Thinking about the call is important but with ebony you have an other concern. DON'T set it is direct sunlight for more than a minute or two regardless of the temperature., especially in a car or truck or at home where sunlight through a window hits it. One side heats and the other side does not - uneven expansion on a wood that cracks so easily.

 

[monophoto]

Fixable? anything is fixable with different ways to do it. As far as preventing, no. That is a wood that is prone to crack and with different conditions as you mentioned is tough to stop no matter what type finish put on it. That piece sees alot more different temp swings and probably wet and dry conditions.

Agree with John - anything is fixable, and one of the challenges I most enjoy about wood turning is devising ways to fix things that don't work out the way you expect.

And wood expands and contracts as its internal moisture content changes with variations in ambient humidity. Go back and watch some of Norm Abrams New Yankee Workshop TV programs - he was constantly concerned about wood movement, and always planned the construction of the furniture he made to minimize the effect of wood movement.

As others have noted, Ebony is one of the woods that cracks more than others. Fruit woods are notorious for cracking, as is birch. So wood selection is one of the factors to consider. Another is the location of the pith - as wood dries, it contracts, and the worst case contraction takes place circumferentially around the pith (ie, across the grain). So if the pith is left in place, the surrounding wood will expand/contract around it resulting in serious cracks. You see this routinely in firewood or if you harvest wood for turning. Hence, removing the pith is always helpful. Larger items are more prone to cracking than smaller items simply because there is more wood to expand or contract.

And cracks are almost inevitable if the thing you are making imposes constraints on wood movement. This is a risk with pens because the wood surrounds a rigid brass tube. Fortunately, most pen blanks are cut excluding the pith, and the amount of wood that remains after the pen is turned is so small that cracking rarely happens. But it is still possible - I have a very nice El Grande fountain pen that has some very small cracks - so small that you have to look very closely to see them, but they are still there. On the other hand, one of the things I do is make decorative pill jars by turning wood sleeves that fit over glass or plastic containers. The jar that holds my daily statin tablet has a major crack (about 1/16" wide) that extends down the side and across the bottom. I made it from wood harvested from a plum tree, and left the pith in the center of the blank, and glued the wooden sleeve over a small glass jar. The audible pop that accompanied when that crack formed was so loud that it woke me from a deep sleep! I keep it as a reminder to always be aware of wood movement when working with wood.